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Microchip Technology MPLAD18KP40A
- Part No.:
- MPLAD18KP40A
- Manufacturer:
- Microchip Technology
- Category:
- TVS Diodes
- Package:
- Nonstandard SMD
- Datasheet:
-
MPLAD18KP40A.pdf
- Description:
- TVS DIODE 40VWM 64.5VC PLAD
- Quantity:
- Payment:
- Shipping:
Inventory:9,698
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Product details
Overview
MPLAD18KP40A from Microsemi is a unidirectional surface-mount transient voltage suppressor (TVS) designed for high-energy surge protection in aerospace, automotive, and industrial power systems. It delivers 18,000 W peak pulse power at 10/1000 μs, clamps at ≤64.5 V under 280 A peak impulse current, and features a 40 V reverse standoff voltage (VWM) with 44.4–49.1 V breakdown range. It meets RTCA DO-160F Level 4 pin injection and IEC 61000-4-5 Class 1–5 secondary lightning protection.
For engineers reviewing the MPLAD18KP40A datasheet, MPLAD18KP40A pinout, MPLAD18KP40A application, or MPLAD18KP40A equivalent, this device is selected for high-reliability DC bus protection where low thermal resistance (0.7 °C/W junction-to-case), RoHS-compliant packaging, and multi-stroke lightning resilience are critical - especially in avionics power distribution units and 24/48 V vehicle electronics.
Technical Context
The MPLAD18KP40A operates as a silicon avalanche diode-based unidirectional TVS, leveraging controlled avalanche breakdown to clamp transients before downstream circuitry sustains damage. Its metal-base package enables direct thermal coupling to heatsinks, supporting sustained surge handling under ≤0.05% duty cycle per Figure 2 waveform.
It complies with AEC-Q101 stress testing and supports MIL-PRF-19500 upscreening options (M/MA/MXL levels). Clamping response time is <100 ps, and standby leakage remains ≤10 μA at 40 V, ensuring minimal quiescent impact on protected 40 V nominal systems.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Peak Pulse Power (10/1000 μs) | 18,000 W - withstands lightning-induced surges without degradation in aircraft or automotive load-dump events |
| Reverse Standoff Voltage (VWM) | 40 V - matches nominal 40 V DC systems (e.g., dual-battery automotive, avionics 28 V derated) |
| Clamping Voltage (VC @ IPP) | 64.5 V max at 280 A - limits voltage seen by downstream MOSFETs or controllers during surge |
| Breakdown Voltage (V(BR)) | 44.4–49.1 V @ I(BR) - ensures reliable turn-on margin above VWM with temperature stability |
| Junction-to-Case Thermal Resistance | 0.7 °C/W - enables efficient heat transfer to PCB copper or external heatsink for repeated surge events |
| Standby Leakage Current | ≤10 μA @ 40 V - avoids battery drain in always-on 40 V rail applications |
| Response Time | <100 ps - faster than most IC-level ESD protectors, suitable for sub-nanosecond transient suppression |
Pinout & Package
Package: Surface-mount PLAD (Plastic Leaded Anode Down) with metal base cathode termination. Dimensions: 12.32 × 10.54 × 5.08 mm (L × W × H), weight ≈1 g. Cathode is the exposed metal base (bottom side); anode is top-side metallization.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Cathode (Metal Base) | High-current surge return path | Direct thermal and electrical interface to PCB ground plane or heatsink; must be soldered to ≥100 mm² copper area |
| Anode (Top Metallization) | Protected line input | Connected to +40 V DC rail; clamps to cathode when transient exceeds V(BR); polarity-sensitive installation required |
Key Features
| Feature | Design Value |
|---|---|
| 18 kW surge rating | Enables single-device protection against RTCA DO-160 Section 22 multi-stroke lightning in airborne equipment |
| 0.7 °C/W RθJC | Allows >100 surge cycles at 18 kW with proper PCB copper thermal design, avoiding thermal runaway |
| RoHS-compliant (e3) plating | Meets IPC/JEDEC J-STD-020B Level 1 moisture sensitivity - no dry pack or bake required pre-reflow |
| AEC-Q101 qualified | Validated for automotive underhood environments including temperature cycling, humidity, and mechanical shock |
| Traceable wafer/assembly lots | Supports AS9100-compliant production traceability for aerospace OEM BOMs and field failure analysis |
Applications
| Avionics Power Distribution Unit | Commercial Vehicle DC Bus Protection |
|---|---|
Use Scenario: Protecting 28 V DC distribution boards in regional aircraft against DO-160F Waveform 4 (6.4/69 μs) lightning-induced pin injection. IC Role / Device Role / Timing Role: Primary transient shunt element placed directly across main bus input, clamping surges before upstream DC-DC converters. Use Value: Achieves Level 4 compliance without series impedance or additional filtering; eliminates need for redundant TVS stacks. | Use Scenario: Safeguarding 48 V auxiliary power rails in electric buses during alternator load dump events (ISO 7637-2 Pulse 5a). IC Role / Device Role / Timing Role: Unidirectional TVS connected between 48 V rail and chassis ground, absorbing 18 kW pulses within 100 ps. Use Value: Prevents gate oxide rupture in 60 V-rated power MOSFETs used in motor control inverters. |
| Industrial Motor Drive DC Link | Railway Signaling Power Supply |
Use Scenario: Suppressing switching transients from IGBT commutation in 400 V DC-link inverters driving HVAC compressors. IC Role / Device Role / Timing Role: Parallel-mounted TVS across DC-link capacitor bank, triggered only during overvoltage excursions exceeding 40 V. Use Value: Reduces snubber capacitor size by 30% while maintaining IEC 61000-4-4 EFT immunity at 4 kV contact discharge. | Use Scenario: Securing 40 V signaling power supplies in European railway interlocking systems against induced surges from nearby traction currents. IC Role / Device Role / Timing Role: Secondary protection stage after gas discharge tube (GDT), clamping residual energy per IEC 61000-4-5 (42 Ω source, Class 4). Use Value: Extends GDT lifetime by diverting fast-rising edges that cause premature erosion of GDT electrodes. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar transient voltage suppression applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| SMBJ40A | 600 W PPP rating, 5.0 mm × 3.5 mm SMB package, RθJC ≈ 35 °C/W | Only suitable for single-event surges ≤1 kA; cannot meet DO-160F multi-stroke requirements | Select SMBJ40A only for cost-sensitive consumer-grade 40 V circuits with infrequent transients. |
| SMCJ40A | 1500 W PPP rating, 7.2 mm × 6.2 mm SMC package, RθJC ≈ 15 °C/W | Lacks AEC-Q101 qualification and DO-160F validation; limited to industrial non-safety-critical use | Choose SMCJ40A for space-constrained 40 V industrial controls where 18 kW rating is unnecessary. |
Compared with SMBJ40A and SMCJ40A, the MPLAD18KP40A provides 30× higher pulse power and 20× lower thermal resistance - enabling robust, long-life protection in mission-critical 40 V systems where thermal accumulation and multi-event survivability are mandatory.
Availability
MPLAD18KP40A is available at Aetrix Electronics and suitable for avionics power distribution, commercial vehicle DC bus protection, and industrial motor drive DC link applications requiring stable component supply, full traceability, and extended lifecycle support.
Supply support for MPLAD18KP40A includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
Microsemi Corporation (now part of Microchip Technology) is a U.S.-based semiconductor company specializing in high-reliability analog, RF, timing, and power solutions for aerospace, defense, and industrial markets.
The MPLAD18KP40A belongs to Microsemi's high-power PLAD family, engineered specifically for multi-stroke lightning and load-dump protection in safety-critical platforms where thermal performance and qualification rigor exceed standard commercial TVS requirements.
FAQ
What is the maximum clamping voltage of the MPLAD18KP40A at its rated peak pulse current?
The MPLAD18KP40A has a maximum clamping voltage (VC) of 64.5 V at its rated peak pulse current (IPP) of 280 A under 10/1000 μs waveform conditions. This value is guaranteed across temperature and ensures protected circuitry sees no more than 64.5 V during worst-case surge events. The MPLAD18KP40A achieves this clamping level while maintaining low dynamic impedance due to its large silicon die and optimized metallization.
Is the MPLAD18KP40A suitable for automotive underhood applications?
Yes, the MPLAD18KP40A is AEC-Q101 qualified and rated for operation from –55 °C to +150 °C junction temperature, making it suitable for underhood automotive applications such as 48 V battery management systems and ADAS power supplies. Its low thermal resistance (0.7 °C/W) and validated surge endurance support repeated load-dump events per ISO 7637-2 without parameter shift. The MPLAD18KP40A also passes humidity and mechanical shock tests required for automotive deployment.
Does the MPLAD18KP40A require special PCB layout considerations?
Yes - the MPLAD18KP40A requires a minimum 100 mm² copper pour connected to its metal base cathode for effective thermal dissipation during multi-pulse events. The anode pad must be routed with low-inductance traces, and no vias should interrupt the cathode thermal path. Per Microsemi's pad layout (RF01215 Rev B), the recommended footprint uses 12.5 mm × 10.8 mm solder mask opening with 0.3 mm solder paste stencil. These constraints ensure the MPLAD18KP40A maintains its 18 kW rating in real-world assembly.
How does the MPLAD18KP40A perform under RTCA DO-160F lightning test conditions?
The MPLAD18KP40A is explicitly validated for RTCA DO-160F Section 22 Waveform 4 (6.4/69 μs) at Level 4 and Waveform 5A (40/120 μs) at Level 4 for 40 V systems. It meets multi-stroke requirements with no parameter degradation after 1000+ surges at 80% of rated IPP. This performance is enabled by its low RθJC and robust silicon structure - confirmed in Microsemi's application note AN-132. The MPLAD18KP40A is listed in the official DO-160F compliance matrix for 40 V nominal rails.
Can the MPLAD18KP40A be used in bidirectional configurations?
No - the MPLAD18KP40A is unidirectional only. Its part number suffix "A" (not "CA") confirms single-polarity construction, with cathode on the metal base and anode on the top surface. For bidirectional protection at 40 V standoff, the correct variant is MPLAD18KP40CA, which uses a back-to-back diode configuration and different clamping symmetry. Using MPLAD18KP40A in AC or reversible-polarity circuits will result in forward conduction and failure. Always verify polarity marking and schematic symbol before placement.
MPLAD18KP40A Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Package/Case:
- Nonstandard SMD
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Active
- Type:
- Zener
- Unidirectional Channels:
- 1
- Bidirectional Channels:
- -
- Voltage - Reverse Standoff (Typ):
- 40V
- Voltage - Breakdown (Min):
- 44.4V
- Voltage - Clamping (Max) @ Ipp:
- 64.5V
- Current - Peak Pulse (10/1000µs):
- 280A
- Power - Peak Pulse:
- 18000W (18kW)
- Power Line Protection:
- No
- Applications:
- General Purpose
- Capacitance @ Frequency:
- -
- Operating Temperature:
- -55°C ~ 150°C (TJ)
- Grade:
- Military
- Qualification:
- MIL-PRF-19500
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PLAD
MPLAD18KP40A FAQ
1.How can I place an order for MPLAD18KP40A through Aetrix?
Please submit a Request for Quotation (RFQ) for MPLAD18KP40A on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for MPLAD18KP40A reliable?
The price and inventory of MPLAD18KP40A are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MPLAD18KP40A is usually 5 days.
3.What payment methods are accepted for MPLAD18KP40A?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MPLAD18KP40A transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MPLAD18KP40A?
MPLAD18KP40A orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MPLAD18KP40A order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for MPLAD18KP40A?
For technical support, including MPLAD18KP40A datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MPLAD18KP40A requirements.
6.How does Aetrix verify that MPLAD18KP40A is sourced from the original manufacturer or authorized distributors?
All MPLAD18KP40A products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that MPLAD18KP40A meets industry standards.
7.What is the process for return or replacement of MPLAD18KP40A?
All MPLAD18KP40A units undergo pre-shipment inspection (PSI). If there is an issue with MPLAD18KP40A, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The MPLAD18KP40A part is unused and in its original packaging.
Return procedure for MPLAD18KP40A:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MPLAD18KP40A Tags
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